Research And Implementation Of A Novel Photovoltaic Micro-Inverter

PV power generation is an important way to exploit and develop clean energy,and the centralized PV inverter has the disadvantages of large volume,high cost and poor reliability,which make it difficult for PV products to be popular in civilian field.Aiming at this problem,this dissertation presents a flyback inverter as the research object,optimizes its working condition,develops a flyback miniature inverter based on soft switching,completes the corresponding hardware design and software design.In this dissertation,produce a 250 W experimental prototype for the corresponding experiment.This design summarizes the advantages and disadvantages of several mainstream micro-inverter topology,and proposes a new type of zero-voltage switching mode single-stage flyback photovoltaic grid-connected inverter,the main circuit of the inverter using flyback topology converter,the secondary side of the switching using bi-directional switches to the primary switch to work in the soft-switching state.At the same time,it will enhance the power transmission capacity of the converter.This design analyzes the circuit working state of the device during the switching cycle and the line cycle.This dissertation completes the system hardware design,including the main circuit device selection,sampling circuit design and control circuit design.The design of the main circuit based on the analysis of small signal model,completed the system software design,including grid-connected current control and maximum power point tracking control.In this design,Simulink software is used to simulate the running characteristics of the circuit topology,to verify the rationality of the main circuit design and the effectiveness of the control system design.And a series of experiments and tests were carried out on the experimental prototype.The experimental results show that the experimental prototype can realize the basic function of the micro inverter.